Electric relay module with aditional removable contact section



ELECTRIC RELAY MODULE WITH ADDITIONAL REMOVABLE CONTACT SECTION Filed Jan. 22, 1964 J. R. BURCH March 29, 1966 3 Sheets-Sheet 1 lNVE/VTOR. JAMES R BURCH,

March 29, 1966 J. R. BURCH 3,243,564

ELECTRIC RELAY MODULE WITH ADDITIONAL REMOVABLE CONTACT SECTION Filed Jan. 22, 1964 3 Sheets-Sheet 2 F'/ 6.4. F/GJT nv VENTOR. JAMES R BURCH,

TTORNEY.

J. R. BURCH March 29, 1966 ELECTRIC RELAY MODULE WITH ADDITIONAL REMOVABLE CONTACT SECTION Filed Jan. 22, 1964 3 Sheets-Sheet 5 //v VENTOR J/lMy. fiunch By W ATTORNEY United States PatentO 3,243,564 ELECTRIC RELAY MODULE WITH ADDITIONAL REMOVABLE CONTACT SECTION James R. Burch, Nrmal,.lll., assignorto General Electric Company, a corporation of New York Filed lan. 22, 1964, Sen-No. 339,430 12 Claims. (Cl. 200-168) My invention relates to electric relays, and more particularly to a sectionalizedelectricrelay havingseparable groupsof fixed contacts and having cooperating movable contacts connected'together in-ganged relation for simultaneous actuation.

In the utilization of multi-contact electric relays it is frequently found desirable to supplement the capabilities ofa single relay by attaching thereto additional groups of cooperating fixed and movable contacts. In this way initially unanticipated or increasing circuit needs of a system can be cared for without the addition of more relays in parallel. Auxiliary relay contact sections have been provided heretofore, but this is commonly done by gauging contact sections in side-by-side relation so that additional panel space is required for added sections. In panel location where such space is not available it has not been possible to provide additional circuits without rebuilding or adding to the control panel.

It'istherefore a principal object of my invention to provide an electric relay having means for adding a contact section without requiring additional panel mounting space.

More particularly, it is an object of my invention to provide a sectional electric relay in which an added contact section may be mounted upon the exposed front'face of a basic relay module thereby to conserve panel mountingspace.

Another object of my invention is to provide an additional contact section for attachment to the exposed front face of a rectangular or block-like basic relay module adapted for close side-by-side mounting with like basic modules.

A further object of my invention is to provide an additional contact section for electric relays which may be quickly and easily mounted for ganged operation without tools and with minimum disturbance to the basic relay module.

It is a more particular object of my invention to provide a snap-on contact section for a basic relay module of the type having a block configuration with an exposed front face providing ready access to both the fixed and movable contacts.

In carrying out my invention in one preferred embodiment, I utilize a basic relay module of the type having a substantially rectangular block-shaped housing adapted for close side-by-side panel mounting with similar modules and presently an exposed front contact surface. The front contact surface of the relay module is slotted to accommodate a movable'contact carrier and also has mounted thereon cooperating fixed contacts. For attachment to such an exposed front surface I provide an auxiliary snap-on housing section also slotted to accommodate an auxiliary movable contact carrier and having mounted thereon fixed contacts cooperating with the auxiliary contact carrier is formed integrally with a substitute contact carrier for the base module, so that when theauxiliary housing is in place the two contact carriers move together as a ganged unit. Such integral formation of the two-part movable contact carrier requires removal of: the single contact carrier otherwise provided in the basic relay module, but this is quite readily accomplished in an exposed face relay of the type described. If desired, of course, the main and auxiliary contact carriers may be removably interlocked in assembled position.

3,243,564 Patented Mar. 29, 1966 Other objects and advantages of my invention will become apparent by referring now to the following de;

tailed description taken in conjunction with the accom-.

FIG; 5 is a fragmentary and elevationalview of the sectional relayshowing the auxiliary housing and dual movable contact element in place.

FIG. 6 -is a side elevational view-- of the'assembled sectional. relay shownatFIGS; 1 and 5.

FIG. 7 is a plan view of the assembled sectional relay.

FIG. 8 is a cross-sectional viewof the assembled sectionaL-relay taken through the median plane 88 -of FIG. 7.

FIG. 9 is a fragmentary cross-sectional view-of the auxiliary relay housing taken in the plane 99 of FIG. 6.

FIG;- 10 is a fragmentary cross-sectional view of the auxiliary relay housing taken in the-plane 10 10 of FIG. 6.

Referring now-to the drawings, I have illustrated-at FIG. 1 a sectional electric relay comprising a main hous-- ing portion 10, an auxiliary housing portion 11 and a dual movable contact member 12. As shown at FIGS;

1 and 2,.the main housing 10 is composed oftwo substantially identical housinghalves 13 and 14 fixedly connected together along a median plane, as by bolts. 15

and 16,10 form a substantially rectangularbody of block-' like configuration. A bottomside 17 of the housing 10 is'adapted to beseatedupon a suitable'base or panel and the opposite front or upper surface is provided with a wide open-ended. slot 18 centrally disposed along the median plane to form inthe front face a recessed passageway. The housing halves-13 and 14 are preferably formed of asuitable molded plastic insulating material and" are recessed internally beneath the slot-'18 to provide whenassembled a cavity within which is disposed an electromagnet and armature best shown at FIG. 8.

As shown atFIG. 8 the electromagnet within the main relay housing 10 comprises .a fixed magnetizable core A cooperatingmovable armature 20 is carried by an L-shaped actuating 19 carrying an energizing winding 19a.

lever 21 pivotally mounted upon the housing at 22. t The lever 21 is biased by means of a spring 23 to separate thearmature 20 from the core-19. The actuating lever 21- is provided also with a finger 24 extending upwardly into thebase of the-slot 18, as shown at FIGS.-1 and 8.-

The slot 18 is of appreciable width anddepth andcon stitutes a recessed passagewaywithin which may beslidably mounted a rectilinearly movable contact carrier, as illustrated at FIGS. 3 and-4. At FIGSJ3 and 4 I have illustrated a single movable contact member formed as an elongated bodyof electric insulating material slida-bly mounted in the-slot 18 andcarrying a plurality of transversely extending movable bridging contacts 26. Thelower surface of thecontact carrier 25 is notched at a protuberance 27 to provide a separable pin and slot connection with thearnrature finger 24. The single contact carrier 25' of FIGS. 3 and. 4 is held against upward displacement, or removal from theslot 18, by an elongated channel-shaped cover member 28 which isformed of -resilient insulating material and snapped in place in opposed pairs of notches 29in the opposite end walls of the housing 10. To provide for positional indication and manual operation the contact carrier 25 of FIGS. 3 and 4 is formed at its upper surface with an upstanding finger 30 which protrudes through a slot 31 in the cover 28.

In addition to the passageway 18 and the recessed electromagnet structure 19, 19a, 20, the relay main housing includes a plurality of electric terminals 35 disposed in two parallel rows on the upper contact surface of the housing parallel to and on opposite sides of the central passageway 18. As best shown at FIG. 2 the central terminal 35 of each row of terminals is connected to the actuating winding 19a, so that these central terminals constitute coil terminals. Each of the remaining terminals 35 has aflixed thereto a contact member 36 extending transversely inwardly from the terminal toward the central passageway 18. Each opposite pair of contacts 36 cooperates with one of the bridging contacts 26 on the movable contact carrier 25. In the plan view of FIG. 2, one end terminal 35 and contact 36 of each row has been omitted to reveal the mounting seats 37 formed integrally with the housing. The terminals 35 and fixed contacts 36 in each main housing portion 13 and 14 are separated from each other by transverse barrier walls 38 formed integrally with each housing part. Mounting bolts 39 at each of the four corners of the main housing 10 provide means for connecting the housing to a suitable panel or other base.

The main housing member 10 provided with a single movable contact member 25. as shown at FIGS. 3 and 4 constitutes a basic relay module of the type having a substantially rectangular block-like body and an exposed upper contact face providing ready access to both fixed and movable contacts. Such a relay is shown and described in a copending patent application Ser. No. 209,015,. filed by James R. Burch and Richard L. Chace on July 11 1962, now Patent Number 3,198,910, which is assigned to the same assignee as the instant application.

My improved sectional relay including the auxiliary contact housing 11 and dual contact member 12 of FIG. 1 is adapted for removable disposition upon the exposed upper contact face of the main housing 10 in a manner to be described hereinafter.

The auxiliary housing section 11 of my improved sectional relay is formed of two substantially identical housing halves 40 and 41 formed of suitably configured insulating material and held in normal engaging relation along a median plane by means of a C-shaped spring 42 (FIG. 10). Each such auxiliary housing portion is formed with an upper longitudinally extending abutment wall 43 and a parallel lower rib 44 (FIG. 9) between which are disposed a plurality of spaced-apart transverse dividing walls or baffles 45 and outwardly tappered end walls 46. The inner edges of the walls 45 and 46 are olfset outwardly from the median plane to provide therebetween and below the abutment walls 43 a longitudinally extending central passageway 47 for reception of a rectilinearly movable contact carrier. The end walls 46 of the auxiliary housing are provided at their lower ends with inwardly projecting and relatively movable latching detents 53 defining spaced-apart lower lips beneath the passageway 47 to retain the movable contact member trapped within the passageway when the auxiliary housing is removed from the main housing, as will be more evident hereinafter. The auxiliary housing halves 40 and 41 may conveniently be formed of any suitable molded plastic insulating material.

The clamping spring 42 is located on the auxiliary housing in the central spaces between pairs of barrier walls 45. In adjacent spaces to each side of the center space on each housing part 40 and 41.there are provided mounting seats 50 for wiring terminals 51. As illustrated at FIGS. 6 and 7, the wiring terminals 51 are thus disposed in two parallel rows on opposite sides of and parallel to the median plane. To each wiring terminal 51 there is fixedly attached a depending contact arm 52 which extends downwardly parallel to the barrier walls 45 to a location adjacent the central passageway 47. The auxiliary housing portions 40 and 41, when assembled together as described above, are held against relative displacement parallel to the median plane by interlocking action of a positioning pin 54 on each abutment wall 43 by a slightly elongated aperture 55 in the opposite abutment wall 43. This is shown at FIG. 9 and also at FIG. 6 where one of the contact terminals 51 has been omitted to uncover the positioning pin 54. The lower side of each auxiliary housing portion 40 and 41 is provided also with a pair of positioning fingers 56 located to straddle the top of one of the transverse barrier walls 38 in the main housing 10 when the auxiliary housing 11 is in assembled position.

The C-shaped connecting spring 42 as shown at FIGS. 6 and 10 is loosely connected to one auxiliary housing portion between the barrier walls 45 nearest the center and snaps over a detent 60 on the other housing portion (FIG. 10). In the demounted position of the auxiliary housing, as shown at FIG. 1, the connecting spring 42 holds the housing halves 40, 41 in planar contact along the central abutment walls 48 with the movable latching detents 53 spaced apart a predetermined maximum distance. These latching detents 53 are adapted to interfit with opposed pairs of fixed detents 61 formed in the end walls of the main housing parts 13 and 14.

A pair of fixed detents 61 is provided in each end wall of the main housing 10 and adjacent opposite upper ends of the main housing passageway 18. These fixed detents 61 are spaced apart a distance somewhat less than the maximum spacing of the movable detents 53 in the unassembled position of the auxiliary housing as shown at FIG. 1. In order to assemble the housings 10 and 11 together the auxiliary housing portions 40 and 41 are pinched together at their lower ends so that they pivot around the engaging lower edges of the parallel abutment Walls 43 thereby to bring the movable detents 53 together and to stress the C-shaped spring 42. With the detents 53 thus brought together, the auxiliary housing parts are brought against the upper contact surface of the main housing 10 and the latching detents 53 inserted into the passageway 18 between the fixed detents 61. When the upper housing parts are released, the C-shaped spring moves the detents 53 apart, bringing them into firm latching engagement with the detents 61. This will be evident from examination of FIGS. 5, 9 and 10.

Having now described the main and auxiliary housing portions of my sectional relay, I will describe in further detail the dual contact-carrier member 12 (FIG. 1) which is entrapped in the auxiliary housing passageway 47 and one part of which is adapted to be substituted, when desired, for the single contact-carrier 25 (FIGS. 3 and 4) of the basic relay module. As shown at FIGS. 1, 5, 8 and 9, the dual contact-carrier 12 is formed of two elongated bar-like body portions 65 and 66 disposed in parallel spaced-apart relation and formed integrally with a planar intermediate web portion 67. Each body portion 65 and 66 carries a plurality of transversely disposed bridging contact members, the bridging contact in the lower body portion 65 being identified by the reference numeral 68, and those in the upper body portion being identified by the reference numeral 69. In the assembled position of the auxiliary housing halves 40 and 41, the upper body portion 66 of the dual contact carrier 12 is entrapped by the inturned detents 53 within the passageway 47 in the auxiliary housing. The lower body portions 65 of the dual contact carrier depends below the auxiliary housing 11 and is adapted for disposition within the passageway 18 in the main housing 10. In the assembled position shown at FIGS. 5, 6, 7 and 8, the upper bridging contacts 69 are disposed for cooperation with the fixed contact members 52 in the auxiliary housing, and the lower bridging contact members 67 are disposed for cooperation with the fixed contact members 36 in the main housing. As shown most clearly at FIG. 8, the lower surface of the lower contact-carrier body 65 is provided with an apertured protuberance 71 for interlocked driving engagement with the armature finger 24 in the same manner as previously described in reference to the single contact-carrier of the basic relay module as shown at FIGS. 3 and 4.

It will now be understood that if it is desired to expand the circuit capabilities of the basic relay module illustrated at FIGS. 2, 3 and 4 by affixing thereto the auxiliary contact housing 11, it is only necessary to remove the snap-on cover member 28 of FIGS. 3 and 4 and lift out the single contact carrier 25. The main housing then presents the appearance shown at FIGS. 1 and 2 with the open passageway 18 along the upper exposed contact surface. In the manner previously described the connected auxiliary housing 11 and dual contact carrier 12 is then clamped in position on the upper surface of the main housing 10 with the contact carrier part 65 disposed in the passageway 18 and the movable latching detents 53 snapped into engagement with the fixed detents 61 in the main housing. All these operations are readily carried out on the exposed upper surface of the main housing 10 and the additional circuit contacts provided in the auxiliary housing 11 are added without requiring any additional panel space. Moreover it will be evident from an examination of FIG. 7 that the upper rows of fixed contact terminals 51 are inwardly offset from the lower rows of fixed contact terminals 35 on the main housing, so that all fixed contact terminals are still readily accessible from the front despite superposition on the front face of the auxiliary housing 11.

While a four-pole relay is shown in the drawings with a four-pole auxiliary housing it will, of course, be evident to those skilled in the art that the number of poles on both the main and auxiliary housings may be increased or decreased as desired without departing from the primary concept of my invention. Moreover, while I have described by way of illustration a dual movable contact carrier formed integrally so that in part it provides a substitute carrier in the main housing, it will be evident that if desired the body portions of the dual carrier may be separable so that no substitution is necessary. Accordingly, therefore, while I have shown and described only a preferred embodiment of my invention by way of illustration, various changes and modifications will occur to those skilled in the art, and that I therefore wish to have it understood that I intend in the appended claims to cover all such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A sectional electroresponsive relay comprising a main housing slotted across one side thereof to provide a recessed main passageway adapted to receive a movable contact member, a first plurality of stationary contacts mounted upon said one side of said main housing adjacent said main passageway, an auxiliary housing memher having an elongated auxiliary passageway therein and .a second plurality of stationary contacts adjacent said auxiliary passageway, a first movable contact body movably mounted within said auxiliary passageway for movement relative to said second plurality of stationary contacts,

means for removably connecting said auxiliary housing upon said one side of said main housing, a second movable contact body movably disposed in said main passageway for movement relative to said first plurality of stationary contacts, and means for effecting movement of said first and second movable contact bodies as a unit relative to said first and second pluralities of stationary contacts when the housings are connected, such that contacts carried by said first and second movable contact bodies are engageable and disengageable with said first and second pluralities of stationary contacts.

2. A sectional electroresponsive relay comprising a main housing slotted across one face thereof to provide a main passageway adapted to receive a movable contact member, a first plurality of stationary contacts mounted upon said one face of said main housing, an auxiliary housing having a second passageway therein and a second plurality of stationary contacts adjacent said second passageway, means removably connecting said main and auxiliary housings with said main and second passageways in parallel spaced relation, movable contact members slidably mounted in each of said passageways and means for effecting movement of said movable contact members as a unit relative to said first and second pluralities of stationary contacts when the housings are connected.

3. A sectional electroresponsive relay comprising an insulating main housing having a cavity therein and an elongated opening extending centrally across one face thereof, said elongated opening constituting a main passageway for a movable contact member, a first pair of spaced-apart rows of fixed contacts mounted upon said main housing at opposite sides of said main passageway, an auxiliary housing removably connected to said main housing upon said one face and having a second elongated passageway formed therein in parallel spaced relation with said main passageway, a second pair of spaced-apart rows of fixed contacts mounted upon said auxiliary housing on opposite sides of said second passageway, first and second elongated movable contact carriers slidably mounted in said main and second passageways respectively, said contact carriers having movable contact members mounted thereon and disposed for cooperation with the juxtaposed rows of fixed contacts, and electroresponsive actuating means mounted in said cavity and having a movable part extending into engagement with the first contact carrier in said main passageway, and means for effecting movement of first and second movable contact carriers as a unit relative to said first and second pairs of spaced apart rows of fixed contacts when the housings are connected.

4. A sectional electroresponsive relay comprising a main housing slotted across one face thereof to provide a recessed main passageway open at one side and adapted to receive a movable contact member, a plurality of stationary contacts mounted upon said one face of said main housing adjacent said main passageway, an auxiliary housing member formed of two substantially identical parts resiliently connected together for relative pivotal movement about a predetermined median line, said auxiliary housing member having a central passageway there- -in and including a plurality of stationary contacts in parallel rows adjacent said central passageway, a dual movable contact member having a first movable contact body portion movably mounted within said central passageway and having a second movable contact body portion, and latching means releasable by pivotal movement of said auxiliary housing parts for removably connecting said assembled auxiliary housing upon said one face of said main housing, said second movable contact body portion when so connected being disposed in said main passageway, whereby contacts carried by said first movable contact body portion are engageable with said plurality of stationary contacts adjacent said central passageway, and contacts carried by said second movable contact body portion are engageable with said plurality of stationary contacts adjacent said main passageway.

5. A sectional electroresponsive relay comprising a main housing slotted across one face thereof to provide a main passageway adapted to receive 'a movable contact member, a plurality'of stationary contacts mounted upon said one faceof said main housing, said main housing in cluding in the region of said one face at least one pair of fixedly spaced-apart latching detents, an auxiliary housing formed of two substantially identical par-ts resiliently held together and relatively pivotally movable about a predetermined line in the median plane thereof, said auxiliary housing including at one side thereof at least one pair of movable latching detents actuable by such pivotal movement and being internally recessed to provide a central passageway therethrough, a plurality of stationary contacts fixed to said auxiliary housing on opposite sides of said central passageway, said pairs of fixed and movable detents providing means for removably attaching said auxiliary housing upon said one face of said main housing with said main and central passageways in parallel spaced relation, a dual movable contact member having interconnected body portions slidably positioned in each of said passageways, whereby when said auxiliary housing is attached to said main housing, contacts carried by said dual movable contact member are engageable with said pluralities of stationary contacts, and electroresponsive actuating means disposed in said main housing to engage and move said dual movable contact member.

6. A sectional electroresponsive relay comprising an insulating main housing having a cavity therein and an elongated opening extending across one face thereof, said elongated opening constituting a main passageway for a movable contact member, a pair of spaced apart rows of fixed contacts including terminal members mounted upon said one face of said main housing at opposite sides of said main passageway, said main housing being formed to provide adjacent opposite ends of said main passageway separate pairs of fixedly spaced-apart latching detents, an auxiliary housing formed of two substantially identical parts resiliently held together along a median plane and relatively pivotally movable about a line in said plane, said auxiliary housing parts being internally recessed adjacent said median plane to form a central passageway open long one side of said auxiliary housing, a second pair of spaced-apart rows of fixed contacts on a said auxiliary housing adjacent said central passgeway,

s aidtauxiliary housing being formed to provide two pairs of relatively movable latching detents adjacent opposite ends of said central passageway for latching cooperation with said pairs of fixed detents on said main housing, said auxiliary housing being adapted to seat upon said one face of said main housing between said rows of terminal members and with said fixed and movable detents in latching engagement and said main and central passageways in spaced-apart relation, a pair of elongated movable contact carriers interconnected and slidably mounted in said main and central passageways respectively, said contact carriers having movable contact members mounted thereon disposed for cooperation with the juxtaposed rows of fixed contacts, and electroresponsive actuating means mounted in said cavity in said main housing and having a movable part extending into engagement with the contact carrier part in said main passageway so as to actuate said interconnected pair of elongated movable contact carriers for movement of said movable contact members relative to said juxtaposed rows of fixed contacts.

7. A sectional electroresponsive relay according to claim 6 in which the movable contact carriers are formed as an integral dual contact carrier having two elongated body portions and an intermediate web portion and in which said auxiliary housing includes means for loosely and slidably retaining one such body portion in said central passageway, the other such body portion being slidably positioned in said main passageway when said main and auxiliary housings are assembled together.

8. A relay according to claim 1 in which the stationary contacts on said main housing include main terminal portions disposed in parallel rows on opposite sides of said main passageway, the stationary contacts on said auxiliary housing include auxiliary terminal portions disposed in parallel rows on opposite sides of said auxiliary passageway, and said auxiliary housing seats upon said one side of said main housing between the rows of main housing contact terminal portions, whereby all main and auxiliary terminal portions are accessible from one side of said sectional relay.

9. A sectional electric relay comprising a main housing including an electroresponsive actuating element and a movable contact member, said movable contact member carrying a plurality of bridging contacts and said housing having mounted thereon a plurality of cooperable fixed contacts, a plurality of terminals mounted in two spacedapart parallel rows along opposite edges of one substantially planar face of said main housing, said terminals being connected to said fixed contacts and to said electroresponsive element, an auxiliary housing member including a second movable contact member removably mounted upon said one face of said main housing between said rows accessible from the one side of said main housing said second movable contact member carrying a plurality of bridging contacts and said auxiliary housing having mounted thereon a plurality of cooperable fixed contacts, a plurality of terminals mounted in two spacedapart parallel rows on said auxiliary housing and connected to the fixed contacts on said auxiliary housing, and means for efiecting movement of said movable contact members together for conjoint operation, said relay when assembled exposing all said terminals in parallel rows accessible from the one side of said main housing upon which said auxiliary housing is mounted.

10. A relay according to claim 1 in which said means for removably connecting said auxiliary housing upon said one side of said main housing comprises fixed latching detents on one of said housings and resiliently biased latching detents on the other of said housings, said resiliently biased latching detents being movable relative to said fixed detents into and out of engagement therewith when said housings are in operative relative position to permit connection and disconnection of said housings.

11. An auxiliary pole adder for releasable attachment to a relay which includes a main housing having mounted therein an electroresponsive actuating means, and a plurality of stationary contacts, said auxiliary pole adder comprising: a housing having an elongated passageway therein and a plurality of stationary contacts adjacent said passageway, a movable contact member having a first movable body portion movably mounted within said passageway and carrying movable contacts which. are engagable with the plurality of stationary contacts adjacent said passageway and a second movable contact body portion carrying movable contacts which are engagable with the plurality of stationary contacts in the main housing, said movable ocntact member being engaged by the electroresponsive actuating means to engage and disengage said pluralities of movable and stationary contacts.

12. A sectional electric relay comprising a main housing including an energizing winding and a first movable contact member, said main housing having at one side thereof a recessed main passageway adapted to receive said first movable contact member, said first movable contact member carrying a first plurality of bridging contacts, a first plurality of fixed contacts mounted on said main housing in two spaced-apart parallel rows on opposite sides of said main passageway engagable with said first plurality of bridging contacts, a first plurality of terminals mounted in two spaced-apart parallel rows along opposite edges of said one side of said main housing, said first plurality of terminals being connected to said first plurality of fixed contacts and to said winding, an auxiliary housing including a second movable contact member, said auxiliary housing formed of two similar parts abutting along a plane generally parallel to said spaced-apart parallel rows of said first pluralities of fixed contacts and terminals, said auxiliary housing being removably mounted upon said one side of said main housing, fixed latching detents on one of said housings and resiliently biased latching detents on the other of said housings, said resiliently biased latching detents being movable relative to said fixed detents into and out of an engagement therewith when said housings are in an operative relative position to permit connection and disconnection of said housings, said auxiliary housing parts being internally recessed adjacent said plane to form a central passageway adapted to receive said second movable contact member, said second movable contact member carrying a second plurality of bridging contacts, a second plurality of fixed contacts mounted on said auxiliary housing in two spaced-apart parallel rows on opposite sides of said central passageway, said second plurality of fixed contacts engagable with said second plurality of bridging contacts, a second plurality of terminals mounted in two spaced-apart parallel rows on said auxiliary housing, said second plurality of terminals being connected to said second plurality of fixed contacts on said auxiliary housing, and means for effecting movement of said first and second movable contact members and the associated first and second pluralities of bridging contacts respectively relative to the said first and second pluralities of fixed contacts in response to energization of said winding when the housings are operatively connected, all of said terminals being accessible from said one side of said main housing when said auxiliary housing is mounted therein.

References Cited by the Examiner UNITED STATES PATENTS 2,616,998 11/1952 Sala 20087 X KATHLEEN H. CLAFFY, Primary Examiner.

H. O. JONES, Assistant Examiner, 

1. A SECTIONAL ELECTRORESPONSIVE RELAY COMPRISING A MAIN HOUSING SLOTTED ACROSS ONE SIDE THEREOF TO PROVIDE A RECESSED MAIN PASSAGEWAY ADAPTED TO RECEIVE A MOVABLE CONTACT MEMBER, A FIRST PLURALITY OF STATIONARY CONTACTS MOUNTED UPON SAID ONE SIDE OF SAID MAIN HOUSING ADJACENT SAID MAIN PASSAGEWAY, AN AUXILIARY HOUSING MEMBER HAVING AN ELONGATED AUXILIARY PASSAGEWAY THEREIN AND A SECOND PLURALITY OF STATIONARY CONTACTS ADJACENT SAID AUXILIARY PASSAGEWAY, A FIRST MOVABLE CONTACT BODY MOVABLY MOUNTED WITHIN SAID AUXILIARY PASSAGEWAY FOR MOVEMENT RELATIVE TO SAID SECOND PLURALITY OF STATIONARY CONTACTS, MEANS FOR REMOVABLY CONNECTING SAID AUXILIARY HOUSING UPON SAID ONE SIDE OF SAID MAIN HOUSING A SECOND MOVABLE CONTACT BODY MOVABLY DISPOSED IN SAID MAIN PASSAGEWAY FOR MOVEMENT RELATIVE TO SAID FIRST PLURALITY OF STATIONARY CONTACTS, AND MEANS FOR EFFECTING MOVEMENT OF SAID FIRST AND SECOND MOVABLE CONTACT BODIES AS A UNIT RELATIVE TO SAID FIRST AND SECOND PLURALITIES OF STATIONARY CONTACTS WHEN THE HOUSINGS ARE CONNECTED, SUCH THAT CONTACTS CARRIED BY SAID FIRST AND SECOND MOVABLE CONTACT BODIES ARE ENGAGEABLE AND DISENGAGEABLE WITH SAID FIRST AND SECOND PLURALITIES OF STATIONARY CONTACTS. 